Anatomical variants of mediastinal organs

Abstract

Background. Variants of mediastinal organs have significant clinical importance in various and numerous medical and surgical contexts. Anatomical variants of mediastinal organs may be congenital or acquired, symptomatic or asymptomatic, and can be mistaken for pathologies on CT, MRI, or ultrasound imaging. Objective(s). Knowledge of mediastinal variants is crucial in thoracic surgery and imageguided interventions to avoid complications, to guide treatment and therapeutic strategy accurately. Materials and methods. A total of 24 mediastinal complexes from the Department of Anatomy and Clinical Anatomy at “Nicolae Testemițanu” State University of Medicine and Pharmacy were analyzed. The study involved 60 patients who underwent advanced imaging investigations, including CT, MRI, and angiography, using data from the Diagnostic Center database. Results. Variants of mediastinal organs were found in all compartments. In the anterior mediastinum, thymus variants included an accessory lobe, persistence in adults, and retrovenous location behind the brachiocephalic vein. In the middle mediastinum, nerve variants involved the phrenic nerve crossing in front of the subclavian vein, an accessory phrenic nerve, and a duplicated left recurrent laryngeal nerve. In the posterior mediastinum, variations were observed in the azygos venous system (such as vein fusion or absence of the accessory hemiazygos vein) and in the thoracic duct (with double, serpiginous, or spiral course). Conclusion(s). All mediastinal organs – viscera, nerves, and blood vessels – may present anatomical variations. Only some of these can be identified preoperatively through imaging. Awareness of such variants is essential for surgeons to avoid intraoperative complications and morbidity.